Link4 · Pearl iDoser

Direct injection fertigation · built for commercial protected production

The clipboard was honest work. This is honest record.

Automatic fertilizer and acid dosing that keeps its own continuous feed record, for commercial greenhouses and nurseries.

Feed gets tracked the way it always has: a sheet on the wall, a spreadsheet at the desk, a person in between. The iDoser doses the recipes you set, keeps the record continuously, and keeps it itself.

Monitor only to start Stops on an out-of-range reading Only a person restarts it
1 to 10 acres under cover 8 to 32 irrigation zones 2 to 6 channels plus acid
An injection skid on its stand
Pearl iDoser on an injection skid.

What it is: a Pearl control direct injection skid.

Plain language first

What direct injection means

The fertilizer never sits in a big batch tank. Concentrated stock solutions stay in their own drums. As irrigation water flows through the line, small precise pumps inject each concentrate directly into the moving water, in proportion to the flow.

The feed is made fresh in the moment it is used. Change the recipe and the next irrigation runs the new one: there is no tank to drain, no batch to remix, and no mixing morning on the calendar.

Who this is not for: recirculating hydroponics. If you run NFT, deep water culture or a recirculating system, that is a different conversation: ask sales about availability. iDoser direct injection is built for drain-to-waste and open irrigation in commercial greenhouses and nurseries.

The concentrates meet the water in the line, already in motion. Illustration.

Where it earns its keep

Built for the crops that punish a feed mistake

Large commercial operations, long rows, thousands of plants on the same line. These are the five places direct injection with a continuous record matters most.

Rows of flowering cannabis plants in a commercial greenhouse

Cannabis and hemp

Multi-room, commercial, licensed. Input logging is expected at every audit. Every injection event is logged with EC, pH, flow and volume, on a timeline nobody had to remember to keep.

A large commercial glasshouse of ornamental crop rows

Floriculture and ornamentals

Bedding, potted, cut. Uniformity between houses decides finish dates. Two zones can be compared on the same chart, feed by feed, instead of by walking them.

Strawberries fruiting in raised substrate gutters in a commercial greenhouse

Berries in substrate

Strawberries, raspberries and blueberries in pots and gutters. Substrate berries are unforgiving on pH and EC, and blueberries live in a narrow acid band. Feed pH is read continuously, logged and alarmed.

Hundreds of young potted plants in rows in a commercial nursery

Container nursery

Long cycles across many zones. Drift hides until the crop shows it. Injector ratios change over time and must be periodically re-verified (University of Georgia Extension, B1237). The chart shows the change when it happens.

Rows of leafy greenhouse vegetables under a steel truss roof

Greenhouse vegetables

Tomatoes, peppers, cucumbers, leafy greens on substrate, drain to waste. Heavy feeders, unforgiving of an EC excursion. The excursion is on the chart as it happens, with alarms to email, text or push.

Not on this list

Recirculating hydroponics. NFT, deep water culture and recirculating systems are a different conversation. Ask sales about availability rather than forcing a fit.

The current state of feed tracking

Three places the feed lives today

On the wall today

Feed log · house 2

6:05aEC 2.1pH 5.9JG
9:50aEC 2.3pH 5.7JG
4:20pEC 2.2pH 5.8TD

lunch rush, catch up Monday

At the desk today

feed-log-2026.xlsx · House 2
DateTimeECpHInit
8/286:05a2.15.9JG
8/289:50a2.35.7JG
8/296:10a2.25.8JG
8/30wknd?
9/016:00a2.45.6TD

Typed up from the sheet, when there is time to type it up.

The record, keeping itself

Simulated data

Every reading, every event, timestamped as it happens. No initials required.

Between initials

The sheet knows two moments. The crop lives in all of them.

6:05a · EC 2.1 · JG
First reading, first initials.
3 hours 45 minutes with no line on the sheet
9:50a · EC 2.3 · JG
Second reading. Whatever happened in between is nobody's to know.

Injector ratios change over time and must be periodically re-verified (University of Georgia Extension, B1237). Drift lives exactly where the sheet is blank.

The iDoser Data Log page: day-long EC, pH, temperature and flow charts, and a log table of irrigation events with start, end, recipe and volume

The same day, kept by the controller: charts of every reading, a log of every event, a CSV when someone asks. Simulated data.

The whole day on one board

See every zone, every feed window, every valve, in one view

Nutrient Alignment lays each irrigation valve against the recipe windows it can draw from, across the whole day. Overlaps are fine: three zones on one header at once is how a large system gets watered. What the board flags is the mismatch, water drawn with no window open, or a window nothing drank.

The iDoser Nutrient Alignment board: irrigation valves for House 1 and House 2 laid across a 24 hour timeline against colored recipe windows, with audit flags reading 2 runs draw water with no window open and 4 windows nothing drank

The Nutrient Alignment board reading a simulated day. The audit is advisory: the grower decides. Simulated data.

The iDoser dashboard tiles on a phone: EC, pH, flow rate and total flow, with the injection cycle status

Simulated data.

The record follows you

The clipboard stayed on its nail. This comes along.

The same tiles, the same charts and the same log, on the phone already in your pocket. Nothing to transcribe at the end of the day, and nothing waiting on the wall.

Email when a reading crosses a limit. Text when it matters right now. Push for everything worth a glance.

checked from the truck, 6:04a

A grower's hands holding a phone at the head of a commercial glasshouse aisle, trellised crop rows and a concrete path behind

Stock photograph.

When someone asks for the record

An auditor does not want the story. They want the log.

Food safety water documentation, cannabis input logging, a uniformity dispute between houses: the answer is a record nobody had to remember to keep. The schedule says what was supposed to happen. The log says what did. The limits say what was never allowed to happen.

The iDoser nutrient availability schedule: recipe windows with times and durations, and the whole day drawn as one colored bar

What was supposed to happen: the schedule, with the day drawn as one bar. Simulated data.

The iDoser dashboard in a stopped state: a red Lockout High status on the EC tile, a fault reset control, and the injection cycle stopped on an EC High limit

What was never allowed: a reading crossed its limit, dosing stopped and stayed stopped. The console's own words: the limits armed and tripped, and nothing restarts injection but a human. Simulated data.

Stated exactly

EC and pH lockout thresholds can be configured to lock out injection and stop the pump on an out-of-range reading.

Trip a lockout yourself in DryRun

Three ways in

Start with the record. Add control when you are ready.

A

Pearl Protect

Monitor only, by design. It reads the skid you already own and never writes to it. The record, the charts and the alarms.

Ships today
B

Pearl Digital

Adds remote control: see EC and pH, change the feed rate, enable or disable feedback dosing, shut dosing down.

C

Full system

Pearl plus a new direct injection skid, quoted per job for your zones, channels and water.

On price: sales quotes each system for the operation in front of them, and payback is worked in months from your own numbers, your flow, your feed, your labor, and the crop you are protecting. Agricultural wages have risen roughly 35% since 2019 (Farm Credit East, 2026 Green Industry Outlook); the hours are the expensive part. Estimate your own payback below.

See what it is worth on your crop

Your numbers, not our brochure

Pick where you are starting. The estimate runs on typical numbers for a commercial grow, and you can open any line to see and change what drives it. It is an estimate, not a guarantee.

Tap any line to see and change what drives it.

Estimated payback
months
Value a month, net$0 / mo
Over a year$0

An estimate from typical numbers, not a guarantee of results. Open any line to put your own figures in. Bring these to sales and they will work it against a real quote.

Backed by Link4

You are not buying a black box from a stranger

  • Over 20 years of Link4 greenhouse control behind the platform, and injection hardware that has been in operations since 1955.
  • A hardware warranty on every system. Ask sales for the current coverage on your configuration.
  • Onsite commissioning available: a Link4 person sets it up on your skid and walks your team through it.
  • A real phone number and people who know the product. Support is support@link4controls.com.
A grower tending vibrant flowering crops in front of a range of commercial glasshouses
Commercial protected production. Stock photograph.

Asked out loud

The questions growers actually ask

What happens if a reading goes out of range?

EC and pH lockout thresholds can be configured to lock out injection and stop the pump on an out-of-range reading. Dosing stays stopped until a person restarts it, and the alarm reaches you by email, text or push.

Does it work with the injection skid I already own?

If you run an Anderson-class skid with a Modbus interface and no other control system on that connection, Pearl Protect reads it without changing how the skid runs. That first question, whether another controller already sits on the skid, is the first thing sales will ask you.

What if I never want it to dose on its own?

Then it never does. Pearl Protect is monitor only by design: it cannot write to the skid. You get the record, the charts and the alarms, and dosing stays exactly as it is today.

Is there a subscription?

Yes. The system includes a Link4 Cloud subscription for the remote view, the continuous record and the alarms, quoted with your system so there is no surprise on the invoice later.

How often do the probes need calibration?

EC and pH probes need periodic calibration, like any such instrument on any fertigation system. Your team can do it, or a Link4 calibration visit can, and the console alarms on an out-of-range reading in between.

Who is behind this?

Link4 Controls, building greenhouse control systems for over 20 years. The injection hardware is built by H.E. Anderson making injection systems since 1955. Pearl reads the skid over Modbus using a register map the manufacturer supplied.

Try it, talk to us, or both

Run the actual console for 30 minutes. Free.

DryRun is the iDoser console over a simulated injection skid: the dashboard, the schedule, the recipes, the valves and the alarms, running a full simulated day. No hardware, no install, nothing to undo.

  • Drive the same screens a grower uses in production
  • Watch EC and pH move as recipes dose a simulated day
  • Trip a lockout on purpose and see what stops
  • Simulated data only: nothing you do touches a real crop

Your session runs 30 minutes once the console loads. You can ask for a call at any point, during the session or instead of one: DryRun is optional.

Two things and you are in

Try it first, on your own. This just unlocks DryRun. We only reach out if you ask us to below.

Tailor my session and help sales prep (optional)

DryRun opens as soon as you submit.

No newsletter, no resale.

Before you decide anything

Fifty-eight seconds of the actual console.

The dashboard, the log, the schedule, the recipes, the valves and the alarms, exactly as they look on screen.

Simulated data
The skid: injection hardware in operations since 1955.
The link: Pearl reads the skid over Modbus using a register map the manufacturer supplied.
The platform: built on the Pearl control platform Link4 has shipped for over 20 years.
The room to grow: 128 outputs, 128 inputs, 128 user-defined controls per zone.

the sheet can retire with honor

Run the console yourself Contact Link4